You’re running up against the inherent limitations of the OH widget and f7 systems. I don’t think there’s a built-in way for you to do this. This is probably possible if you are really determined but it will almost definitely require some un-official javascript methods (see this topic).
You certainly cannot easily add the ability to zoom to any widget that does not already have that capability because the setting of the main OH page deactivates basic browser zoom actions. So, it would require significant custom js scripting to add that feature individually to elements.
If there is any remotely reasonable path to this at all, it would be through a simple script that forces the f7 photo browser to refresh the image. You might even able to combine this with something like this so you wouldn’t have worry about creating and destroying your own js timer intervals.
Honestly, if I were trying to create something like this, I would take 1 of 2 paths: 1) Create a quick independent web app that then is just loaded in an oh-webframe (maybe an LLM can even get you most of the way there pretty quickly at this point, I don’t know), or 2) create a PR for the oh webui that adds a refresh interval as a possible configuration to the photos action.